Multi-speed planetary transmission

ABSTRACT

A multi-speed transmission including a plurality of planetary gearsets and a plurality of selective couplers to achieve at least nine forward speed ratios is disclosed. The plurality of planetary gearsets may include a first planetary gearset, a second planetary gearset, a third planetary gearset, and a fourth planetary gearset. The plurality of selective couplers may include a number of clutches and a number of brakes. The multi-speed transmission may have four planetary gearsets and six selective couplers. The six selective couplers may include three clutches and three brakes.

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Ser.No. 62/400,932, filed Sep. 28, 2016, titled MULTI-SPEED PLANETARYTRANSMISSION, the entire disclosure of which is expressly incorporatedby reference herein.

FIELD OF THE DISCLOSURE

The present disclosure relates to a multi-speed transmission and inparticular to a multi-speed transmission including a plurality ofplanetary gearsets and a plurality of selective couplers to achieve atleast nine forward speed ratios and at least one reverse speed ratio.

BACKGROUND OF THE DISCLOSURE

Multi-speed transmissions use a plurality of planetary gearsets,selective couplers, interconnectors, and additional elements to achievea plurality of forward and reverse speed ratios. Exemplary multi-speedtransmissions are disclosed in US Published Patent Application No.2016/0047440, Ser. No. 14/457,592, titled MULTI-SPEED TRANSMISSION,filed Aug. 12, 2014, the entire disclosure of which is expresslyincorporated by reference herein.

SUMMARY

The present disclosure provides a multi-speed transmission including aplurality of planetary gearsets and a plurality of selective couplers toachieve at least nine forward speed ratios. The plurality of planetarygearsets may include a first planetary gearset, a second planetarygearset, a third planetary gearset, and a fourth planetary gearset. Theplurality of selective couplers may include a number of clutches and anumber of brakes. In one example, the present disclosure provides amulti-speed transmission having four planetary gearsets and sixselective couplers. The six selective couplers include three clutchesand three brakes.

In some instances throughout this disclosure and in the claims, numericterminology, such as first, second, third, and fourth, is used inreference to various gearsets, gears, gearset components,interconnectors, selective couplers, and other components. Such use isnot intended to denote an ordering of the components. Rather, numericterminology is used to assist the reader in identifying the componentbeing referenced and should not be narrowly interpreted as providing aspecific order of components. For example, a first planetary gearsetidentified in the drawings may support any one of the plurality ofplanetary gearsets recited in the claims, including the first planetarygearset, the second planetary gearset, the third planetary gearset, andthe fourth planetary gearset, depending on the language of the claims.

According to an exemplary embodiment of the present disclosure, atransmission is provided. The transmission comprising an input member; aplurality of planetary gearsets operatively coupled to the input member;a plurality of selective couplers operatively coupled to the pluralityof planetary gearsets, each of the plurality of selective couplershaving an engaged configuration and a disengaged configuration; and anoutput member operatively coupled to the input member through theplurality of planetary gearsets. Each planetary gearset of the pluralityof planetary gearsets including a sun gear, a plurality of planet gearsoperatively coupled to the sun gear, a planet carrier operativelycoupled to the plurality of planet gears, and a ring gear operativelycoupled to plurality of planet gears. The plurality of planetarygearsets including a first planetary gearset, a second planetarygearset, a third planetary gearset, and a fourth planetary gearset. Theoutput member is fixedly coupled to one of the plurality of planetarygearsets. A first selective coupler of the plurality of selectivecouplers fixedly couples at least two of the sun gear, the planetcarrier, and the ring gear of the one of the plurality of planetarygearsets together and to the output member when the first selectivecoupler is in the engaged configuration.

According to another exemplary embodiment of the present disclosure, atransmission is provided. The transmission comprising at least onestationary member; an input member rotatable relative to the at leastone stationary member; and a plurality of planetary gearsets operativelycoupled to the input member. Each of the plurality of planetary gearsetsincludes a first gearset component, a second gearset component, and athird gearset component. The plurality of planetary gearsets including afirst planetary gearset, a second planetary gearset, a third planetarygearset, and a fourth planetary gearset. The input member is fixedlycoupled to the second gearset component of the second planetary gearset.The transmission further comprising an output member operatively coupledto the input member through the plurality of planetary gearsets androtatable relative to the at least one stationary member, the outputmember is fixedly coupled to the third gearset component of the firstplanetary gearset; a first interconnector fixedly couples the firstgearset component of the first planetary gearset with the third gearsetcomponent of the second planetary gearset; a second interconnectorfixedly couples the second gearset component of the first planetarygearset with the second gearset component of the third planetarygearset; a third interconnector fixedly couples the third gearsetcomponent of the third planetary gearset with the second gearsetcomponent of the fourth planetary gearset; a first selective couplerwhich, when engaged, fixedly couples a first one of the first gearsetcomponent of the first planetary gearset, the second gearset componentof the first planetary gearset, and the third gearset component of thefirst planetary gearset to a second one of the first gearset componentof the first planetary gearset, the second gearset component of thefirst planetary gearset, and the third gearset component of the firstplanetary gearset; a second selective coupler which, when engaged,fixedly couples the second gearset component of the fourth planetarygearset to the second gearset component of the second planetary gearset;a third selective coupler which, when engaged, fixedly couples the firstgearset component of the second planetary gearset to the at least onestationary member; a fourth selective coupler which, when engaged,fixedly couples the second gearset component of the fourth planetarygearset to the first gearset component of the second planetary gearset;a fifth selective coupler which, when engaged, fixedly couples the firstgearset component of the fourth planetary gearset to the at least onestationary member; and a sixth selective coupler which, when engaged,fixedly couples the first gearset component of the third planetarygearset to the at least one stationary member.

According to a further exemplary embodiment of the present disclosure, atransmission is provided. The transmission comprising at least onestationary member; an input member rotatable relative to the at leastone stationary member; and a plurality of planetary gearsets operativelycoupled to the input member. The plurality of planetary gearsetsincluding: a first planetary gearset including a first sun gear, a firstplanet carrier, a first plurality of planet gears operatively coupled tothe first sun gear and operatively coupled to the first planet carrier,and a first ring gear operatively coupled to the first plurality ofplanet gears; a second planetary gearset including a second sun gear, asecond planet carrier, a second plurality of planet gears operativelycoupled to the second sun gear and operatively coupled to the secondplanet carrier, and a second ring gear operatively coupled to the secondplurality of planet gears; a third planetary gearset including a thirdsun gear, a third planet carrier, a third plurality of planet gearsoperatively coupled to the third sun gear and operatively coupled to thethird planet carrier, and a third ring gear operatively coupled to thethird plurality of planet gears; and a fourth planetary gearsetincluding a fourth sun gear, a fourth planet carrier, a fourth pluralityof planet gears operatively coupled to the fourth sun gear andoperatively coupled to the fourth planet carrier, and a fourth ring gearoperatively coupled to the fourth plurality of planet gears. Thetransmission further comprising a plurality of selective couplersoperatively coupled to the plurality of planetary gearsets, each of theplurality of selective couplers having an engaged configuration and adisengaged configuration, and an output member operatively coupled tothe input member through the plurality of planetary gearsets androtatable relative to the at least one stationary member. The outputmember being fixedly coupled to the first planetary gearset. Theplurality of selective couplers are selectively engaged in combinationsof at least three to establish at least nine forward speed ratios and atleast one reverse speed ratio between the input member and the outputmember. In a first speed ratio of the at least nine forward speed ratiosa subset of the plurality of selective couplers are engaged to fixedlycouple each of the second sun gear of the second planetary gearset, thethird sun gear of the third planetary gearset, and the fourth sun gearof the fourth planetary gearset to the at least one stationary member.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of thisdisclosure, and the manner of attaining them, will become more apparentand will be better understood by reference to the following descriptionof exemplary embodiments taken in conjunction with the accompanyingdrawings, wherein:

FIG. 1 is a diagrammatic view of an exemplary multi-speed transmissionincluding four planetary gearsets and six selective couplers; and

FIG. 2 is a truth table illustrating the selective engagement of the sixselective couplers of FIG. 1 to provide ten forward gear or speed ratiosand a reverse gear or speed ratio of the multi-speed transmission ofFIG. 1.

Corresponding reference characters indicate corresponding partsthroughout the several views. The exemplification set out hereinillustrates an exemplary embodiment of the invention and suchexemplification is not to be construed as limiting the scope of theinvention in any manner.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of thepresent disclosure, reference is now made to the embodiment illustratedin the drawings, which is described below. The embodiment disclosedbelow is not intended to be exhaustive or limit the present disclosureto the precise form disclosed in the following detailed description.Rather, the embodiment is chosen and described so that others skilled inthe art may utilize its teachings. Therefore, no limitation of the scopeof the present disclosure is thereby intended. Corresponding referencecharacters indicate corresponding parts throughout the several views.

In the disclosed transmission embodiment, selective couplers aredisclosed. A selective coupler is a device which may be actuated tofixedly couple two or more components together. A selective couplerfixedly couples two or more components to rotate together as a unit whenthe selective coupler is in an engaged configuration. Further, the twoor more components may be rotatable relative to each other when theselective coupler is in a disengaged configuration. The terms “couples”,“coupled”, “coupler” and variations thereof are used to include botharrangements wherein the two or more components are in direct physicalcontact and arrangements wherein the two or more components are not indirect contact with each other (e.g., the components are “coupled” viaat least a third component), but yet still cooperate or interact witheach other.

A first exemplary selective coupler is a clutch. A clutch couples two ormore rotating components to one another so that the two or more rotatingcomponents rotate together as a unit in an engaged configuration andpermits relative rotation between the two or more rotating components inthe disengaged position. Exemplary clutches may be shiftablefriction-locked multi-disk clutches, shiftable form-locking claw orconical clutches, wet clutches, or any other known form of a clutch.

A second exemplary selective coupler is a brake. A brake couples one ormore rotatable components to a stationary component to hold the one ormore rotatable components stationary relative to the stationarycomponent in the engaged configuration and permits rotation of the oneor more components relative to the stationary component in thedisengaged configuration. Exemplary brakes may be configured asshiftable-friction-locked disk brakes, shiftable friction-locked bandbrakes, shiftable form-locking claw or conical brakes, or any otherknown form of a brake.

Selective couplers may be actively controlled devices or passivedevices. Exemplary actively controlled devices include hydraulicallyactuated clutch or brake elements and electrically actuated clutch orbrake elements. Additional details regarding systems and methods forcontrolling selective couplers are disclosed in the above-incorporatedUS Published Patent Application No. 2016/0047440.

In addition to coupling through selective couplers, various componentsof the disclosed transmission embodiments may be fixedly coupledtogether continuously throughout the operation of the disclosedtransmissions. Components may be fixedly coupled together eitherpermanently or removably. Components may be fixedly coupled togetherthrough spline connections, press fitting, fasteners, welding, machinedor formed functional portions of a unitary piece, or other suitablemethods of connecting components.

The disclosed transmission embodiments include a plurality of planetarygearsets. Each planetary gearset includes at least four components: asun gear; a ring gear; a plurality of planet gears; and a carrier thatis rotatably coupled to and carries the planet gears. In the case of asimple planetary gearset, the teeth of the sun gear are intermeshed withthe teeth of the planet gears which are in turn engaged with the teethof the ring gear. Each of these components may also be referred to as agearset component. It will be apparent to one of skill in the art thatsome planetary gearsets may include further components than thoseexplicitly identified. For example, one or more of the planetarygearsets may include two sets of planet gears. A first set of planetgears may intermesh with the sun gear while the second set of planetgears intermesh with the first set of planet gears and the ring gear.Both sets of planet gears are carried by the planet carrier.

One or more rotating components, such as shafts, drums, and othercomponents, may be collectively referred to as an interconnector whenthe one or more components are fixedly coupled together. Interconnectorsmay further be fixedly coupled to one or more gearset components and/orone or more selective couplers.

An input member of the disclosed transmission embodiments is rotated bya prime mover. Exemplary prime movers include internal combustionengines, electric motors, hybrid power systems, and other suitable powersystems. In one embodiment, the prime mover indirectly rotates the inputmember through a clutch and/or a torque converter. An output member ofthe disclosed transmission embodiments provides rotational power to oneor more working components. Exemplary working components include one ormore drive wheels of a motor vehicle, a power take-off shaft, and othersuitable devices. The output member is rotated based on theinterconnections of the gearset components and the selective couplers ofthe transmission. By changing the interconnections of the gearsetcomponents and the selective couplers, a rotation speed of the outputmember may be varied from a rotation speed of the input member.

The disclosed transmission embodiment is capable of transferring torquefrom the input member to the output member and rotating the outputmember in at least nine forward gear or speed ratios relative to theinput member, illustratively ten forward gear or speed ratios, and onereverse gear or speed ratio wherein the rotation direction of the outputmember is reversed relative to its rotation direction for the at leastnine forward ratios. Exemplary gear ratios that may be obtained usingthe embodiments of the present disclosure are disclosed herein. Ofcourse, other gear ratios are achievable depending on thecharacteristics of the gearsets utilized. Exemplary characteristicsinclude respective gear diameters, the number of gear teeth, and theconfigurations of the various gears.

FIG. 1 is a diagrammatic representation of a multi-speed transmission100. Multi-speed transmission 100 includes an input member 102 and anoutput member 104. Each of input member 102 and output member 104 isrotatable relative to at least one stationary member 106. An exemplaryinput member 102 is an input shaft or other suitable rotatablecomponent. An exemplary output member 104 is an output shaft or othersuitable rotatable component. An exemplary stationary member 106 is ahousing of multi-speed transmission 100. The housing may include severalcomponents coupled together.

Multi-speed transmission 100 includes a plurality of planetary gearsets,illustratively a first planetary gearset 108, a second planetary gearset110, a third planetary gearset 112, and a fourth planetary gearset 114.In one embodiment, additional planetary gearsets may be included.Further, although first planetary gearset 108, second planetary gearset110, third planetary gearset 112, and fourth planetary gearset 114 areillustrated as simple planetary gearsets, it is contemplated thatcompound planetary gearsets may be included in some embodiments.

In one embodiment, multi-speed transmission 100 is arranged asillustrated in FIG. 1, with first planetary gearset 108 positionedbetween a first location or end 116 at which input member 102 entersstationary member 106 and second planetary gearset 110, second planetarygearset 110 is positioned between first planetary gearset 108 and thirdplanetary gearset 112, third planetary gearset 112 is positioned betweensecond planetary gearset 110 and fourth planetary gearset 114, andfourth planetary gearset 114 is positioned between third planetarygearset 112 and a second location or end 118 at which output member 104exits stationary member 106. In alternative embodiments, first planetarygearset 108, second planetary gearset 110, third planetary gearset 112,and fourth planetary gearset 114 are arranged in any order relative tolocation 116 and location 118. In the illustrated embodiment of FIG. 1,each of first planetary gearset 108, second planetary gearset 110, thirdplanetary gearset 112, and fourth planetary gearset 114 are axiallyaligned. In one example, input member 102 and output member 104 are alsoaxially aligned with first planetary gearset 108, second planetarygearset 110, third planetary gearset 112, and fourth planetary gearset114. In alternative embodiments, one or more of input member 102, outputmember 104, first planetary gearset 108, second planetary gearset 110,third planetary gearset 112, and fourth planetary gearset 114 are offsetand not axially aligned with the remainder.

First planetary gearset 108 includes a sun gear 120, a planet carrier122 supporting a plurality of planet gears 124, and a ring gear 126.Second planetary gearset 110 includes a sun gear 130, a planet carrier132 supporting a plurality of planet gears 134, and a ring gear 136.Third planetary gearset 112 includes a sun gear 140, a planet carrier142 supporting a plurality of planet gears 144, and a ring gear 146.Fourth planetary gearset 114 includes a sun gear 150, a planet carrier152 supporting a plurality of planet gears 154, and a ring gear 156.

Multi-speed transmission 100 further includes a plurality of selectivecouplers, illustratively a first selective coupler 162, a secondselective coupler 164, a third selective coupler 166, a fourth selectivecoupler 168, a fifth selective coupler 170, and a sixth selectivecoupler 172. In one embodiment, the plurality of selective couplersincludes an equal number of brakes and clutches. In the illustratedembodiment, third selective coupler 166, fifth selective coupler 170,and sixth selective coupler 172 are brakes and first selective coupler162, second selective coupler 164, and fourth selective coupler 168 areclutches. The axial locations of the clutches and brakes relative to theplurality of planetary gearsets may be altered from the illustratedaxial locations.

Multi-speed transmission 100 includes several components that areillustratively shown as being fixedly coupled together. Input member 102is fixedly coupled to planet carrier 132 of second planetary gearset110. Output member 104 is fixedly coupled to ring gear 126 of firstplanetary gearset 108. Sun gear 120 of first planetary gearset 108 isfixedly coupled to ring gear 136 of second planetary gearset 110 and toring gear 156 of fourth planetary gearset 114. Planet carrier 122 offirst planetary gearset 108 is fixedly coupled to planet carrier 142 ofthird planetary gearset 112. Ring gear 146 of third planetary gearset112 is fixedly coupled to planet carrier 152 of fourth planetary gearset114. Sun gear 130 of second planetary gearset 110 is fixedly coupled tothird selective coupler 166 and fourth selective coupler 168. Sun gear150 of fourth planetary gearset 114 is fixedly coupled to fifthselective coupler 170. Sun gear 140 of third planetary gearset 112 isfixedly coupled to sixth selective coupler 172. In alternativeembodiments, one or more of the components fixedly coupled together areselectively coupled together through one or more selective couplers.

Multi-speed transmission 100 may be described as having eightinterconnectors. Input member 102 is a first interconnector that bothprovides input torque to multi-speed transmission 100 and fixedlycouples planet carrier 132 of second planetary gearset 110 to secondselective coupler 164. Output member 104 is a second interconnector thatboth provides output torque from multi-speed transmission 100 andfixedly couples ring gear 126 of first planetary gearset 108 to firstselective coupler 162. A third interconnector 180 fixedly couples sungear 120 of first planetary gearset 108, ring gear 136 of secondplanetary gearset 110, and ring gear 156 of fourth planetary gearset 114together. A fourth interconnector 182 fixedly couples planet carrier 142of third planetary gearset 112, planet carrier 122 of first planetarygearset 108, and first selective coupler 162 together. A fifthinterconnector 184 fixedly couples ring gear 146 of third planetarygearset 112, planet carrier 152 of fourth planetary gearset 114, secondselective coupler 164, and fourth selective coupler 168 together. Asixth interconnector 186 fixedly couples sun gear 130 of secondplanetary gearset 110 to third selective coupler 166 and fourthselective coupler 168. A seventh interconnector 188 fixedly couples sungear 150 of fourth planetary gearset 114 to fifth selective coupler 170.An eighth interconnector 190 fixedly couples sun gear 140 of thirdplanetary gearset 112 to sixth selective coupler 172.

Multi-speed transmission 100 further includes several components thatare illustratively shown as being selectively coupled together throughselective couplers. First selective coupler 162, when engaged, fixedlycouples planet carrier 122 of first planetary gearset 108 to ring gear126 of first planetary gearset 108 through interconnector 182 and hencefixedly couples planet carrier 122 of first planetary gearset 108 tooutput member 104. When first selective coupler 162 is engaged, planetcarrier 122 and ring gear 126 of first planetary gearset 108 are lockedtogether. When first selective coupler 162 is disengaged, planet carrier122 of first planetary gearset 108 may rotate relative to ring gear 126of first planetary gearset 108.

As mentioned, when first selective coupler 162 is engaged, planetcarrier 122 of first planetary gearset 108 and ring gear 126 of firstplanetary gearset 108 are locked together. Hence, sun gear 120, planetcarrier 122, and ring gear 126 of first planetary gearset 108 all rotatetogether as a single unit. The same effect may be realized by couplingany two of sun gear 120, planet carrier 122, and ring gear 126 together.In one example, first selective coupler 162 is fixedly coupled to ringgear 126 of first planetary gearset 108 and sun gear 120 of firstplanetary gearset 108. In this example, when first selective coupler 162is engaged, ring gear 126 of first planetary gearset 108 and sun gear120 of first planetary gearset 108 are locked together resulting in allof sun gear 120, planet carrier 122, and ring gear 126 of firstplanetary gearset 108 rotating together as a single unit. In anotherexample, first selective coupler 162 is fixedly coupled to sun gear 120of first planetary gearset 108 and planet carrier 122 of first planetarygearset 108. In this example, when first selective coupler 162 isengaged, sun gear 120 of first planetary gearset 108 and planet carrier122 of first planetary gearset 108 are locked together resulting in allof sun gear 120, planet carrier 122, and ring gear 126 of firstplanetary gearset 108 rotating together as a single unit.

Second selective coupler 164, when engaged, fixedly couples planetcarrier 152 of fourth planetary gearset 114 to planet carrier 132 ofsecond planetary gearset 110 and hence to input member 102.Additionally, ring gear 146 of third planetary gearset 112 is fixedlycoupled to input member 102 when second selective coupler 164 is engagedthrough interconnector 184. When second selective coupler 164 isdisengaged, planet carrier 152 of fourth planetary gearset 114 mayrotate relative to planet carrier 132 of second planetary gearset 110and hence relative to input member 102.

Third selective coupler 166, when engaged, fixedly couples sun gear 130of second planetary gearset 110 to stationary member 106. When thirdselective coupler 166 is disengaged, sun gear 130 of second planetarygearset 110 may rotate relative to at least one stationary member 106.

Fourth selective coupler 168, when engaged, fixedly couples planetcarrier 152 of fourth planetary gearset 114 to sun gear 130 of secondplanetary gearset 110. When fourth selective coupler 168 is disengaged,planet carrier 152 of fourth planetary gearset 114 may rotate relativeto sun gear 130 of second planetary gearset 110.

Fifth selective coupler 170, when engaged, fixedly couples sun gear 150of fourth planetary gearset 114 to stationary member 106. When fifthselective coupler 170 is disengaged, sun gear 150 of fourth planetarygearset 114 may rotate relative to at least one stationary member 106.

Sixth selective coupler 172, when engaged, fixedly couples sun gear 140of third planetary gearset 112 to at least one stationary member 106.When sixth selective coupler 172 is disengaged, sun gear 140 of thirdplanetary gearset 112 may rotate relative to at least one stationarymember 106.

By engaging various combinations of first selective coupler 162, secondselective coupler 164, third selective coupler 166, fourth selectivecoupler 168, fifth selective coupler 170, and sixth selective coupler172, additional components of multi-speed transmission 100 may befixedly coupled together.

The plurality of planetary gearsets and the plurality of selectivecouplers of multi-speed transmission 100 may be interconnected invarious arrangements to provide torque from input member 102 to outputmember 104 in at least nine forward gear or speed ratios and one reversegear or speed ratio. Referring to FIG. 2, an exemplary truth table 200is shown that provides the state of each of first selective coupler 162,second selective coupler 164, third selective coupler 166, fourthselective coupler 168, fifth selective coupler 170, and sixth selectivecoupler 172 for ten different forward gear or speed ratios and onereverse gear or speed ratio. Each row corresponds to a giveninterconnection arrangement for transmission 100. The first columnprovides the gear range (reverse and 1^(st)-10^(th) forward gears). Thesecond column provides the gear ratio between the input member 102 andthe output member 104. The third column provides the gear step. The sixrightmost columns illustrate which ones of the selective couplers162-172 are engaged (“1” indicates engaged) and which ones of selectivecouplers 162-172 are disengaged (“(blank)” indicates disengaged). FIG. 2is only one example of any number of truth tables possible for achievingat least nine forward ratios and one reverse ratio.

In the example of FIG. 2, the illustrated reverse ratio (Rev) isachieved by having first selective coupler 162, third selective coupler166, and sixth selective coupler 172 in an engaged configuration andsecond selective coupler 164, fourth selective coupler 168, and fifthselective coupler 170 in a disengaged configuration.

In one embodiment, to place multi-speed transmission 100 in neutral(Neu), all of first selective coupler 162, second selective coupler 164,third selective coupler 166, fourth selective coupler 168, fifthselective coupler 170, and sixth selective coupler 172 are in thedisengaged configuration. One or more of first selective coupler 162,second selective coupler 164, third selective coupler 166, fourthselective coupler 168, fifth selective coupler 170, and sixth selectivecoupler 172 may remain engaged in neutral (Neu) as long as thecombination of first selective coupler 162, second selective coupler164, third selective coupler 166, fourth selective coupler 168, fifthselective coupler 170, and sixth selective coupler 172 does not transmittorque from input member 102 to output member 104.

A first forward ratio (shown as 1st) in truth table 200 of FIG. 2 isachieved by having second selective coupler 164, third selective coupler166, and sixth selective coupler 172 in an engaged configuration andfirst selective coupler 162, fourth selective coupler 168, and fifthselective coupler 170 in a disengaged configuration.

A second or subsequent forward ratio (shown as 2nd) in truth table 200of FIG. 2 is achieved by having first selective coupler 162, secondselective coupler 164, and third selective coupler 166 in an engagedconfiguration and fourth selective coupler 168, fifth selective coupler170, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the first forward ratio and thesecond forward ratio, sixth selective coupler 172 is placed in thedisengaged configuration and first selective coupler 162 is placed inthe engaged configuration.

A third or subsequent forward ratio (shown as 3rd) in truth table 200 ofFIG. 2 is achieved by having second selective coupler 164, thirdselective coupler 166, and fourth selective coupler 168 in an engagedconfiguration and first selective coupler 162, fifth selective coupler170, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the second forward ratio and thethird forward ratio, first selective coupler 162 is placed in thedisengaged configuration and fourth selective coupler 168 is placed inthe engaged configuration.

A fourth or subsequent forward ratio (shown as 4th) in truth table 200of FIG. 2 is achieved by having first selective coupler 162, thirdselective coupler 166, and fourth selective coupler 168 in an engagedconfiguration and second selective coupler 164, fifth selective coupler170, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the third forward ratio and thefourth forward ratio, second selective coupler 164 is placed in thedisengaged configuration and first selective coupler 162 is placed inthe engaged configuration.

A fifth or subsequent forward ratio (shown as 5th) in truth table 200 ofFIG. 2 is achieved by having third selective coupler 166, fourthselective coupler 168, and sixth selective coupler 172 in an engagedconfiguration and first selective coupler 162, second selective coupler164, and fifth selective coupler 170 in a disengaged configuration.Therefore, when transitioning between the fourth forward ratio and thefifth forward ratio, first selective coupler 162 is placed in thedisengaged configuration and sixth selective coupler 172 is placed inthe engaged configuration.

A sixth or subsequent forward ratio (shown as 6th) in truth table 200 ofFIG. 2 is achieved by having third selective coupler 166, fourthselective coupler 168, and fifth selective coupler 170 in an engagedconfiguration and first selective coupler 162, second selective coupler164, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the fifth forward ratio and thesixth forward ratio, sixth selective coupler 172 is placed in thedisengaged configuration and fifth selective coupler 170 is placed inthe engaged configuration.

A seventh or subsequent forward ratio (shown as 7th) in truth table 200of FIG. 2 is achieved by having third selective coupler 166, fifthselective coupler 170, and sixth selective coupler 172 in an engagedconfiguration and first selective coupler 162, second selective coupler164, and fourth selective coupler 168 in a disengaged configuration.Therefore, when transitioning between the sixth forward ratio and theseventh forward ratio, fourth selective coupler 168 is placed in thedisengaged configuration and sixth selective coupler 172 is placed inthe engaged configuration.

An eighth or subsequent forward ratio (shown as 8th) in truth table 200of FIG. 2 is achieved by having second selective coupler 164, fifthselective coupler 170, and sixth selective coupler 172 in an engagedconfiguration and first selective coupler 162, third selective coupler166, and fourth selective coupler 168 in a disengaged configuration.Therefore, when transitioning between the seventh forward ratio and theeighth forward ratio, third selective coupler 166 is placed in thedisengaged configuration and second selective coupler 164 is placed inthe engaged configuration.

A ninth or subsequent forward ratio (shown as 9th) in truth table 200 ofFIG. 2 is achieved by having first selective coupler 162, secondselective coupler 164, and fifth selective coupler 170 in an engagedconfiguration and third selective coupler 166, fourth selective coupler168, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the eighth forward ratio and theninth forward ratio, sixth selective coupler 172 is placed in thedisengaged configuration and first selective coupler 162 is placed inthe engaged configuration.

A tenth or subsequent forward ratio (shown as 10th) in truth table 200of FIG. 2 is achieved by having second selective coupler 164, fourthselective coupler 168, and fifth selective coupler 170 in an engagedconfiguration and first selective coupler 162, third selective coupler166, and sixth selective coupler 172 in a disengaged configuration.Therefore, when transitioning between the ninth forward ratio and thetenth forward ratio, first selective coupler 162 is placed in thedisengaged configuration and fourth selective coupler 168 is placed inthe engaged configuration.

The present disclosure contemplates that downshifts follow the reversesequence of the corresponding upshift (as described above). Further,several power-on skip-shifts that are single-transition are possible(e.g. from 1^(st) up to 3^(rd), from 3^(rd) down to 1^(st), from 3^(rd)up to 5^(th), and from 5^(th) down to 3^(rd)).

In the illustrated embodiments, various combinations of three of theavailable selective couplers are engaged for each of the illustratedforward speed ratios and reverse speed ratios. Additional forward speedratios and reverse speed ratios are possible based on other combinationsof engaged selective couplers. Although in the illustrated embodiments,each forward speed ratio and reverse speed ratio has three of theavailable selective couplers engaged, it is contemplated that less thanthree and more than three selective couplers may be engaged at the sametime.

While this invention has been described as having exemplary designs, thepresent invention can be further modified within the spirit and scope ofthis disclosure. This application is therefore intended to cover anyvariations, uses, or adaptations of the invention using its generalprinciples. Further, this application is intended to cover suchdepartures from the present disclosure as come within known or customarypractice in the art to which this invention pertains and which fallwithin the limits of the appended claims.

What is claimed is:
 1. A transmission comprising: an input member; aplurality of planetary gearsets operatively coupled to the input member,each planetary gearset of the plurality of planetary gearsets includinga sun gear, a plurality of planet gears operatively coupled to the sungear, a planet carrier operatively coupled to the plurality of planetgears, and a ring gear operatively coupled to the plurality of planetgears, the plurality of planetary gearsets including a first planetarygearset, a second planetary gearset, a third planetary gearset, and afourth planetary gearset; a plurality of selective couplers operativelycoupled to the plurality of planetary gearsets, each of the plurality ofselective couplers having an engaged configuration and a disengagedconfiguration, the plurality of selective couplers including a firstnumber of brakes and a second number of clutches, the first number equalto the second number; and an output member operatively coupled to theinput member through the plurality of planetary gearsets, wherein theoutput member is fixedly coupled to one of the plurality of planetarygearsets and a first selective coupler of the plurality of selectivecouplers fixedly couples at least two of the sun gear, the planetcarrier, and the ring gear of the one of the plurality of planetarygearsets together and to the output member when the first selectivecoupler is in the engaged configuration.
 2. The transmission of claim 1,wherein the output member is fixedly coupled to the ring gear of the oneof the plurality of planetary gearsets.
 3. The transmission of claim 2,wherein the first selective coupler fixedly couples the ring gear of theone of the plurality of planetary gearsets to the planet carrier of theone of the plurality of planetary gearsets when the first selectivecoupler is in the engaged configuration.
 4. The transmission of claim 2,wherein the planet carrier of the one of the plurality of planetarygearsets is fixedly coupled to the planet carrier of another one of theplurality of planetary gearsets.
 5. The transmission of claim 1, whereinthe plurality of selective couplers are selectively engaged in aplurality of combinations to establish at least nine forward speedratios and at least one reverse speed ratio between the input member andthe output member, each of the plurality of combinations having at leastthree of the plurality of selective couplers engaged.
 6. Thetransmission of claim 5, wherein each of the at least nine forward speedratios between the input member and the output member is one of lessthan unity and greater than unity.
 7. The transmission of claim 5,wherein the first selective coupler of the plurality of selectivecouplers is in the engaged configuration for a first one of the at leastnine forward speed ratios having a first speed ratio and a second one ofthe at least nine forward speed ratios having a second speed ratio, atleast a third one of the at least nine forward speed ratios having athird speed ratio which is greater than the first speed ratio and lessthan the second speed ratio, the first selective coupler being in thedisengaged configuration for the third one of the at least nine forwardspeed ratios.
 8. The transmission of claim 5, further comprising atleast one stationary member, wherein the plurality of selective couplersinclude a plurality of brakes, the plurality of brakes being engaged ina first one of the at least nine forward speed ratios to fixedly couplethe sun gear of the second planetary gearset, the sun gear of the thirdplanetary gearset, and the sun gear of the fourth planetary gearset tothe at least one stationary member.
 9. The transmission of claim 1,wherein the plurality of selective couplers further includes a secondselective coupler, a third selective coupler, a fourth selectivecoupler, a fifth selective coupler and a sixth selective coupler. 10.The transmission of claim 9, wherein the first selective coupler is afirst clutch.
 11. The transmission of claim 9, further comprising ahousing, wherein the input member is fixedly coupled to the planetcarrier of the second planetary gearset; the output member is fixedlycoupled to the ring gear of the first planetary gearset; the sun gear ofthe first planetary gearset is fixedly coupled to the ring gear of thesecond planetary gearset and fixedly coupled to the ring gear of thefourth planetary gearset; the planet carrier of the first planetarygearset is fixedly coupled to the planet carrier of the third planetarygearset; the ring gear of the third planetary gearset is fixedly coupledto the planet carrier of the fourth planetary gearset; the firstselective coupler selectively couples a first one of the sun gear of thefirst planetary gearset, the ring gear of the first planetary gearset,and the planet carrier of the first planetary gearset to a second one ofthe sun gear of the first planetary gearset, the ring gear of the firstplanetary gearset, and the planet carrier of the first planetarygearset; the second selective coupler selectively couples the planetcarrier of the second planetary gearset to the planet carrier of thefourth planetary gearset; the third selective coupler selectivelycouples the sun gear of the second planetary gearset to the housing; thefourth selective coupler selectively couples the sun gear of the secondplanetary gearset to the planet carrier of the fourth planetary gearset;the fifth selective coupler selectively couples the sun gear of thefourth planetary gearset to the housing; and the sixth selective couplerselectively couples the sun gear of the third planetary gearset to thehousing.
 12. The transmission of claim 11, wherein the housing has afirst end and a second end, wherein the input member is accessibleproximate the first end of the housing; the output member is accessibleproximate the second end of the housing; the first planetary gearset ispositioned between the first end of the housing and the second planetarygearset; the second planetary gearset is positioned between the firstplanetary gearset and the third planetary gearset; the third planetarygearset is positioned between the second planetary gearset and thefourth planetary gearset; and the fourth planetary gearset is positionedbetween the third planetary gearset and the second end of the housing.13. A transmission comprising: at least one stationary member; an inputmember rotatable relative to the at least one stationary member; aplurality of planetary gearsets operatively coupled to the input member,each of the plurality of planetary gearsets including a first gearsetcomponent, a second gearset component, and a third gearset component,the plurality of planetary gearsets including a first planetary gearset,a second planetary gearset, a third planetary gearset, and a fourthplanetary gearset, the input member is fixedly coupled to the secondgearset component of the second planetary gearset; an output memberoperatively coupled to the input member through the plurality ofplanetary gearsets and rotatable relative to the at least one stationarymember, the output member is fixedly coupled to the third gearsetcomponent of the first planetary gearset; a first interconnector fixedlycouples the first gearset component of the first planetary gearset withthe third gearset component of the second planetary gearset; a secondinterconnector fixedly couples the second gearset component of the firstplanetary gearset with the second gearset component of the thirdplanetary gearset; a third interconnector fixedly couples the thirdgearset component of the third planetary gearset with the second gearsetcomponent of the fourth planetary gearset; a first selective couplerwhich, when engaged, fixedly couples a first one of the first gearsetcomponent of the first planetary gearset, the second gearset componentof the first planetary gearset, and the third gearset component of thefirst planetary gearset to a second one of the first gearset componentof the first planetary gearset, the second gearset component of thefirst planetary gearset, and the third gearset component of the firstplanetary gearset; a second selective coupler which, when engaged,fixedly couples the second gearset component of the fourth planetarygearset to the second gearset component of the second planetary gearset;a third selective coupler which, when engaged, fixedly couples the firstgearset component of the second planetary gearset to the at least onestationary member; a fourth selective coupler which, when engaged,fixedly couples the second gearset component of the fourth planetarygearset to the first gearset component of the second planetary gearset;a fifth selective coupler which, when engaged, fixedly couples the firstgearset component of the fourth planetary gearset to the at least onestationary member; and a sixth selective coupler which, when engaged,fixedly couples the first gearset component of the third planetarygearset to the at least one stationary member.
 14. The transmission ofclaim 13, wherein each of the first planetary gearset, second planetarygearset, third planetary gearset, and fourth planetary gearset is asimple planetary gearset.
 15. The transmission of claim 13, wherein thefirst gearset component of the first planetary gearset is a first sungear, the first gearset component of the second planetary gearset is asecond sun gear, the first gearset component of the third planetarygearset is a third sun gear, the first gearset component of the fourthplanetary gearset is a fourth sun gear, the second gearset component ofthe first planetary gearset is a first planet carrier, the secondgearset component of the second planetary gearset is a second planetcarrier, the second gearset component of the third planetary gearset isa third planet carrier, the second gearset component of the fourthplanetary gearset is a fourth planet carrier, the third gearsetcomponent of the first planetary gearset is a first ring gear, the thirdgearset component of the second planetary gearset is a second ring gear,the third gearset component of the third planetary gearset is a thirdring gear, and the third gearset component of the fourth planetarygearset is a fourth ring gear.
 16. A transmission comprising: at leastone stationary member; an input member rotatable relative to the atleast one stationary member; a plurality of planetary gearsetsoperatively coupled to the input member, the plurality of planetarygearsets including: a first planetary gearset including a first sungear, a first planet carrier, a first plurality of planet gearsoperatively coupled to the first sun gear and operatively coupled to thefirst planet carrier, and a first ring gear operatively coupled to thefirst plurality of planet gears; a second planetary gearset including asecond sun gear, a second planet carrier, a second plurality of planetgears operatively coupled to the second sun gear and operatively coupledto the second planet carrier, and a second ring gear operatively coupledto the second plurality of planet gears; a third planetary gearsetincluding a third sun gear, a third planet carrier, a third plurality ofplanet gears operatively coupled to the third sun gear and operativelycoupled to the third planet carrier, and a third ring gear operativelycoupled to the third plurality of planet gears; and a fourth planetarygearset including a fourth sun gear, a fourth planet carrier, a fourthplurality of planet gears operatively coupled to the fourth sun gear andoperatively coupled to the fourth planet carrier, and a fourth ring gearoperatively coupled to the fourth plurality of planet gears; a pluralityof selective couplers operatively coupled to the plurality of planetarygearsets, each of the plurality of selective couplers having an engagedconfiguration and a disengaged configuration; an output memberoperatively coupled to the input member through the plurality ofplanetary gearsets and rotatable relative to the at least one stationarymember, the output member being fixedly coupled to the first planetarygearset, wherein the plurality of selective couplers are selectivelyengaged in combinations of at least three to establish at least nineforward speed ratios and at least one reverse speed ratio between theinput member and the output member, in a first speed ratio of the atleast nine forward speed ratios a subset of the plurality of selectivecouplers are engaged to fixedly couple each of the second sun gear ofthe second planetary gearset, the third sun gear of the third planetarygearset, and the fourth sun gear of the fourth planetary gearset to theat least one stationary member.
 17. The transmission of claim 16,wherein the second sun gear of the second planetary gearset, the thirdsun gear of the third planetary gearset, and the fourth sun gear of thefourth planetary gearset are each fixedly coupled to the at least onestationary member only through the subset of the plurality of selectivecouplers.
 18. The transmission of claim 17, wherein the subset of theplurality of selective couplers includes a first brake which, whenengaged, fixedly couples the second sun gear of the second planetarygearset to the at least one stationary member, a second brake which,when engaged, fixedly couples the third sun gear of the third planetarygearset to the at least one stationary member, and a third brake which,when engaged, fixedly couples the fourth sun gear of the fourthplanetary gearset to the at least one stationary member.
 19. Thetransmission of claim 17, wherein the output member is fixedly coupledto a first one of the first sun gear, the first planet carrier, and thefirst ring gear and the output member is further fixedly coupled to asecond one of the first sun gear, the first planet carrier, and thefirst ring gear when a first clutch is engaged.
 20. The transmission ofclaim 19, wherein the output member is fixedly coupled to the first ringgear.
 21. A transmission comprising: at least one stationary member; aninput member rotatable relative to the at least one stationary member; aplurality of planetary gearsets operatively coupled to the input member,each planetary gearset of the plurality of planetary gearsets includinga sun gear, a plurality of planet gears operatively coupled to the sungear, a planet carrier operatively coupled to the plurality of planetgears, and a ring gear operatively coupled to the plurality of planetgears, the plurality of planetary gearsets including a first planetarygearset, a second planetary gearset, a third planetary gearset, and afourth planetary gearset; a plurality of selective couplers operativelycoupled to the plurality of planetary gearsets, each of the plurality ofselective couplers having an engaged configuration and a disengagedconfiguration; and an output member rotatable relative to the at leastone stationary member and operatively coupled to the input memberthrough the plurality of planetary gearsets, wherein the output memberis fixedly coupled to the ring gear of one of the plurality of planetarygearsets and a first selective coupler of the plurality of selectivecouplers fixedly couples the ring gear of the one of the plurality ofplanetary gearsets and the output member to the planet carrier of theone of the plurality of planetary gearsets when the first selectivecoupler is in the engaged configuration, a second selective coupler ofthe plurality of selective couplers fixedly couples a sun gear of asecond one of the plurality of planetary gearsets to the at least onestationary member when the second selective coupler is in the engagedconfiguration, and a third selective coupler of the plurality ofselective couplers fixedly couples a sun gear of a third one of theplurality of planetary gearsets to the at least one stationary memberwhen the third selective coupler is in the engaged configuration.
 22. Atransmission comprising: at least one stationary member; an input memberrotatable relative to the at least one stationary member; a plurality ofplanetary gearsets operatively coupled to the input member, eachplanetary gearset of the plurality of planetary gearsets including a sungear, a plurality of planet gears operatively coupled to the sun gear, aplanet carrier operatively coupled to the plurality of planet gears, anda ring gear operatively coupled to the plurality of planet gears, theplurality of planetary gearsets including a first planetary gearset, asecond planetary gearset, a third planetary gearset, and a fourthplanetary gearset; a plurality of selective couplers operatively coupledto the plurality of planetary gearsets, each of the plurality ofselective couplers having an engaged configuration and a disengagedconfiguration, the plurality of selective couplers including a pluralityof brakes; and an output member rotatable relative to the at least onestationary member and operatively coupled to the input member throughthe plurality of planetary gearsets, wherein the output member isfixedly coupled to one of the plurality of planetary gearsets and afirst selective coupler of the plurality of selective couplers fixedlycouples at least two of the sun gear, the planet carrier, and the ringgear of the one of the plurality of planetary gearsets together and tothe output member when the first selective coupler is in the engagedconfiguration, wherein the plurality of selective couplers areselectively engaged in a plurality of combinations to establish at leastnine forward speed ratios and at least one reverse speed ratio betweenthe input member and the output member, each of the plurality ofcombinations having at least three of the plurality of selectivecouplers engaged, wherein the plurality of brakes being engaged in afirst one of the at least nine forward speed ratios to fixedly couplethe sun gear of the second planetary gearset, the sun gear of the thirdplanetary gearset, and the sun gear of the fourth planetary gearset tothe at least one stationary member.
 23. The transmission of claim 21,wherein the input member is fixedly coupled to a planet carrier of afourth one of the plurality of planetary gearsets.
 24. The transmissionof claim 23, wherein the first one of the plurality of planetarygearsets is the first planetary gearset, the second one of the pluralityof planetary gearsets is the third planetary gearset, the third one ofthe plurality of planetary gearsets is the fourth planetary gearset, andthe fourth one of the plurality of planetary gearsets is the secondplanetary gearset.
 25. The transmission of claim 24, wherein the atleast one stationary member includes a housing having a first end and asecond end, wherein the first planetary gearset is positioned betweenthe first end of the housing and the second planetary gearset; thesecond planetary gearset is positioned between the first planetarygearset and the third planetary gearset; the third planetary gearset ispositioned between the second planetary gearset and the fourth planetarygearset; and the fourth planetary gearset is positioned between thethird planetary gearset and the second end of the housing.